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Osteochondral defects are most commonly characterized by damages to both cartilage and underlying subchondral bone tissues, thus developing bi-layered scaffold that can concurrently regenerate these two specific lineages becomes challenge. In this study, the highly biomimetic bi-layered scaffolds were successfully prepared using human-like-collagen (HLC), hyaluronan (HA) and nano hydroxyapatite (HAP) particles, combined with "liquid phase synthesis" technology, freeze-drying and chemical cross-linking techniques, which was simulated the composition of natural extracellular matrix to repair osteochondral defects. This novel bilayer osteochondral graft had a seamlessly integrated layer structure, suitable pore size, high levels of porosity, and excellent mechanical properties. In vitro cell experiments of the bilayer scaffold indicated that the scaffold could promote the proliferation and adhesion of human bone marrow mesenchymal stem cells. In vivo osteochondral defects and micro-CT experiment revealed that bilayer scaffolds showed complete closure of the defect. Histology confirmed collagen and glycosaminoglycans were deposited in the new matrix of hyaline cartilage and bone in the bilayer scaffold group. Therefore, the developed bionic bilayer scaffold enhanced the regeneration of hyaline cartilage through subchondral bone formation and lateral host-tissue integration. In conclusion, this bilayer scaffold based on HLC could be used as the desired strategy for osteochondral defects regeneration. [ABSTRACT FROM AUTHOR]

Conversion of clean solar energy to chemical fuels is one of the promising and up-and-coming applications of metal–organic frameworks. However, fast recombination of photogenerated charge carriers in these frameworks remains the most significant limitation for their photocatalytic application. Although the construction of homojunctions is a promising solution, it remains very challenging to synthesize them. Herein, we report a well-defined hierarchical homojunction based on metal–organic frameworks via a facile one-pot synthesis route directed by hollow transition metal nanoparticles. The homojunction is enabled by two concentric stacked nanoplates with slightly different crystal phases. The enhanced charge separation in the homojunction was visualized by in-situ surface photovoltage microscopy. Moreover, the as-prepared nanostacks displayed a visible-light-driven carbon dioxide reduction with very high carbon monooxide selectivity, and excellent stability. Our work provides a powerful platform to synthesize capable metal–organic framework complexes and sheds light on the hierarchical structure-function relationships of metal–organic frameworks. Homojunctions are very promising in photocatalysis, but challenging to achieve. Herein, authors report a well-defined hierarchical metal–organic framework-based homojunction, formed via a one-pot synthesis route directed by hollow transition metal nanoparticles, as photocatalysts for CO2 reduction. [ABSTRACT FROM AUTHOR]

In this paper, we consider a fully nonlinear curvature flow of a convex hypersurface in the Euclidean 𝑛-space. This flow involves 𝑘-th elementary symmetric function for principal curvature radii and a function of support function. Under some appropriate assumptions, we prove the long-time existence and convergence of this flow. As an application, we give the existence of smooth solutions to the Orlicz–Christoffel–Minkowski problem. [ABSTRACT FROM AUTHOR]

Vesicular photothermal therapy agents (PTAs) are highly desirable in photothermal therapy (PTT) for their excellent light-harvesting ability and versatile hollow compartments. However, up to now, the reported vesicular PTAs are generally self-assembled from small molecules like liposomes, and polymer vesicles have seldom been used as PTAs due to the unsatisfactory photothermal conversion efficiency resulting from the irregular packing of chromophores in the vesicle membranes. Here we report a nano-sized polymer vesicle from hyperbranched polyporphyrins with favorable photothermal stability and extraordinarily high photothermal efficiency (44.1%), showing great potential in imaging-guided PTT for tumors through in vitro and in vivo experiments. These excellent properties are attributed to the in situ supramolecular polymerization of porphyrin units inside the vesicle membrane into well-organized 1D monofilaments driven by π–π stacking. We believe the supramolecular polymerization-enhanced self-assembly process reported here will shed a new light on the design of supramolecular materials with new structures and functions. Photothermal therapy (PTT) has recently emerged as a promising approach for cancer therapy. Here, the authors report a hyperbranched polymer vesicle with favorable photothermal stability and high photothermal efficiency for PTT through a supramolecular polymerization-enhanced self-assembly strategy. [ABSTRACT FROM AUTHOR]

In this study, we fabricated multifunctionalized hydrogel scaffolds based on hyaluronic acid (HA)-tyrosine and human-like collagen (HLC) by crosslinking with 1, 4-butanedioldiglycidyl ether (BDDE) for soft tissue fillers. The physicochemical of HA-tyrosine/BDDE (HTB) and various proportions of HA-tyrosine/BDDE/HLC (HTBH) hydrogels were characterized by swelling ratio, mechanical strength, morphology and thermal stability. The results demonstrated various HTBH hydrogels had superior performance in mechanical properties than HTB hydrogels. The biodegradation in vitro results demonstrated the degradation of HTBH hydrogels were slower than HTB hydrogels, and residual masses of HTBH hydrogels varied with different proportions of HA-tyrosine and HLC in the presence of the combination of HAse/collagenase I. The cell counting kit-8 (CCK-8), Hoechst/PI staining and cell adhesion of various HTBH hydrogels showed less cytotoxic and superior fibroblast attachment than those of HTB hydrogels. Moreover, subcutaneous injections of HTBH hydrogels containing high proportions of HLC in mice and rabbits all exhibit better biocompatibility and anti-biodegradation compared to HTB hydrogels after 1, 4, 8, 12 and 16 weeks. Hematoxylin-eosin staining (H&E), immunohistochemical and transmission electron microscope (TEM) analysis results indicated HTBH hydrogels had less intense inflammatory responses with increase proportion of HLC. Taken together, HTBH hydrogels had great potential application as ideal soft tissue fillers with excellent mechanical properties, biological stability and biocompatibility. [ABSTRACT FROM AUTHOR]

Ginsenoside Rg5, a rare saponin belonging to the family of protopanaxadiol ginsenosides, has been demonstrated to have potential anti-tumor effects in various cancers. However, the effect of Rg5 on human gastric cancer and the underlying molecular mechanisms remain to be elucidated. In this study, Rg5 could suppress cell proliferation by causing G2/M phase arrest. Treatment with Rg5 could induce apoptosis through the extrinsic death receptor and intrinsic mitochondrial pathways. Autophagy induction was demonstrated by the formation of autophagosomes and autophagy-related proteins. Rg5-induced cell death was inhibited by the autophagy inhibitor 3-MA and apoptosis inhibitor Z-VAD-FMK. Moreover, the suppression of apoptosis weakened Rg5-induced autophagy, while the inhibition of autophagy attenuated Rg5-induced apoptosis. Further studies revealed that Rg5 induced ROS production and activated MAPK signaling pathways. The ROS scavenger NAC markedly diminished G2/M arrest, apoptosis, autophagy and activation of MAPK pathways induced by Rg5. The p38 inhibitor SB203580 or knockdown of p38 by siRNA clearly reversed Rg5-induced apoptosis and G2/M arrest. The JNK inhibitor SP600125 or knockdown of JNK by siRNA markedly attenuated Rg5-induced G2/M arrest, apoptosis and autophagy. The inhibition of ERK inhibitor U0126 or knockdown of ERK by siRNA clearly restored Rg5-induced apoptosis and autophagy. Finally, Rg5 significantly suppressed the growth of xenograft gastric tumors with fewer side effects. Overall, the evidence suggested that Rg5 is a novel and promising strategy for the treatment of gastric cancer owing to its high efficacy, multiple mechanisms and fewer side effects. [ABSTRACT FROM AUTHOR]

Aim at the low real-time performance and high false alarm rate of the traditional fall detection model, AdaBoost multi-core support vector machine model (ADB-MKSVM) was proposed which was used to detect and identify the falling action. Based on the improved AdaBoost model framework, the model took multi-core support vector machine as the basis classifier and assembled these basis classifiers to form a stronger final classifier. According to the distribution of human movement data and whether the classification of each sample in each training set is correct or not, and the overall classification accuracy last time, the weight of each sample was determined. The dynamic weight allocation method was used to improve the recognition rate of the fall action. The test results showed that this model had good classification performance, and the method of binding the sensor on the waist position could effectively improve the detection effect of the fall action. The accuracy rate was 99. 33%,the fall detection rate was 63. 6%,and the false detection rate was 1. 62% . [ABSTRACT FROM AUTHOR]